Pressure source and systems incorporating it

ABSTRACT

A pressure source for providing a stream of liquid at a substantial pressure. The pressure source includes pressurizing means such as a piston-cylinder assembly to which a force is applied to expel the contents thereof under pressure to form the stream. Weight means moving from an upper elevation to a lower elevation provides the said force. The pressure source also includes means to release, in discrete quantums of mass, the weight means for downward movement, in the preferred embodiments, without substantial impediment other than the pressurizing means. This provides sufficient force to supply a stream at a usefully high pressure, for example one which can drive a turbine wheel or a linear actuator at a useful velocity. In a preferred form, the weight means is a buoyant body, and the pressure source includes lift means to float the buoyant body to the upper elevation, and then to permit it to descend to the lower elevation. Systems which can utilize this power source include rotary shaft drives such as turbines, linear shaft drives (linear actuators), and rotary devices driven by linear drives through unidirectional transmission elements (one-way clutches). The systems may also include driven elements such as electrical generators.

This invention relates to a pressure source that produces a stream ofliquid under pressure. The stream can be utilized to power a rotaryshaft drive such as a turbine, or a linear shaft drive such as a linearactuator, or a rotary device driven by a linear actuator through aunidirectional transmission element such as a one-way clutch. The drivenelement may comprise an electrical generator. The invention comprehendsthe pressure source, and also the systems which incorporate it.

It is an object of this invention to provide a pressure source thatproduces a stream of liquid at a usefully high pressure at a usefulvelocity, for example one which can drive a working turbine wheel,utilizing sources of energy that are ordinarily regarded as marginal orunsuitable. One example of such a source of energy is a stream having arelatively low gradient or water head at the site. Another example is apond of tidal water trapped at high tide.

It is another object of this invention to provide a pressure sourcewhich can be constructed from conventional and common materials ofconstruction.

It is still another objective of this invention to provide elegantlysimple controls and components for the pressure source and for systemsthat incorporate it which require a minimum of supervision, maintenanceand repair.

A pressure source according to this invention includes pressurizingmeans, for example a piston-cylinder assembly, to which a force isapplied to expel the contents therefrom as a stream under pressure.Weight means moving from an upper to a lower elevation provides the saidforce. The pressure source also includes means to release, in discretequantums of mass, the weight means for downward movement preferably, butnot necessarily, without substantial impediment other than thepressurizing means. This provides sufficient force to supply a stream offluid under a usefully high pressure.

According to a preferred but optional feature of the invention, theweight means is a buoyant body, and the pressure source includes liftmeans including a flotation tank in which to float the buoyant body tothe upper elevation, and then to permit it to descend to the lowerelevation.

According to still another preferred but optional feature of theinvention, the means to release the weight means comprises a controlexerted on the water level in the flotation tank.

The above and other features of this invention will be fully understoodfrom the following detailed description and the accompanying drawings inwhich:

FIG. 1 is a cross-section taken at line 1--1 of FIG. 3 showing part of asystem according to the invention in one condition;

FIG. 2 is a portion of FIG. 1 showing parts thereof in other positions;

FIG. 3 is a plan view of FIG. 1, partly in schematic notation;

FIG. 4 is a cross-section showing a part of the invention;

FIG. 5 is a top plan view of FIG. 4, partly in schematic notation andpartly in cutaway cross-section;

FIG. 6 is a portion of FIG. 1 showing parts thereof in still otherpositions;

FIG. 7 is a portion of FIG. 1 showing an optional control, partly inschematic notation;

FIG. 8 is an axial cross-section of an alternate construction ofpressurizing means useful in this invention;

FIG. 9 is a cross-section, primarily in plan view and partly inschematic notation, showing another system according to the invention;

FIG. 10 is a cross-section view taken at line 10--10 in FIG. 9;

FIG. 11 is a perspective view of still another system according to theinvention;

FIG. 12 is a side elevation of a part of FIG. 11, partly in cutawaycross-section;

FIG. 13 is a cross-section taken at line 13--13 in FIG. 11;

FIG. 14 is a top view of FIG. 13 with certain parts shown in phantomline;

FIG. 15 is an end view of a part of FIG. 12 taken at line 15--15therein;

FIG. 16 is a side view, principally in axial cross-section, showingalternative means for use in the system of FIG. 11;

FIG. 17 is a side elevation, partly in schematic notation, showing stillother alternative means for use in the system of FIG. 11;

FIG. 18 is a side elevation, primarily in axial cross-section, ofanother embodiment of the invention;

FIG. 19 is a cross-section taken at line 19--19 of FIG. 18; and

FIGS. 20 and 21 are fragmentary side elevations, partly in cutawaycross-section, showing still other embodiments of the invention.

FIG. 1 shows the presently preferred embodiment of the invention, andthe best mode of practicing the same which is presently known to theinventor. The source of energy for the system is a supply of waterhaving an upper supply elevation and a lower drain elevation. Betweenthese two elevations, a body having mass is raised by buoyancy and then,in a non-buoyant condition, is released so as to be applied topressurizing means to produce a stream of liquid under pressure withoutsubstantial impediment other than the pressurizing means. The resultingstream can be used to drive a shaft drive, such as a turbine with anoutput shaft that can be engaged to a driven element, such as anelectrical generator. In this example, the energy from the stream isconverted to electricity. It is evident that other types of drivenelements could instead be driven by power derived from the pressuresource.

With reference to FIG. 1, a flotation tank 26 is shown which is suppliedwith water or other liquid from a supply 20. For operation of thesystem, there is an upper supply elevation 21 in the tank, and a lowerdrain elevation 22. When the system is operated, the water level in thetank is cycled between these two elevations. The actual placement ofthese elevations relative to the water supply and drain, and thedifferential of elevation between them, are determined by the parametersof the system, such as attainable flow rate and attainable supply anddrain elevation.

The elevation 23 of the water supply must be at least as high aselevation 21, which is to say that the tank must be placed andproportioned so that the highest level expected to be reached in thetank is not higher than the supply elevation. The maximum elevation 24of the drain must be at least as low as the lowest level expected to bereached in the tank in operation, which is to say that the tank must beplaced and proportioned so that the lowest working level is not belowthe outside drain level, or the system would not flow.

Of course, in practice, the actual elevation 23 of the water supply willbe higher than elevation 21 in the tank to provide for practical flowrates without pumping into the tank, and the elevation 24 of the drainoutside the tank will be lower than elevation 22 in the tank, again toprovide for practical flow rates without pumping. However, the systemextracts energy as a consequence of flotation in the tank, and any headbetween elevations 21 and 23, and elevations 22 and 24 does not producepower. Therefore, the closer elevation 21 is to elevation 23, and thecloser elevation 22 is to elevation 24, the greater will be theproportion of the available potential energy of the water supply whichis connected to a pressurized system.

The system requires a supply of water and inlet conduitry which willbring the level of water in the tank to elevation 21 in a suitableperiod of time, and a drain level and conduitry which will drain thetank in a suitable period of time.

In a typical installation, the upper supply elevation may represent aninlet weir from a river or stream, and the lower drain elevation mayconstitute a return gate to the same river or stream downstream. It mayalso represent a storage tank filled from a stream or some other supplysuch as windmill-pumped water fed to a tank, or a pond of tidal waterstored at high tide, later to be released to the ocean at low tide.

Importantly, in this invention supplies having comparatively low waterheads on the order of as little as a foot or two can efficiently beutilized, because this invention does not utilize pressure from a streamof water of high head, such as used in common Penstock mechanisms atconventional dams, but rather a high-pressure stream whose pressure isderived from the descent of a mass which was previously raised, in thepreferred embodiment by buoyant means floated in water from the supply.Any desired mass can be floated by buoyant means, and then can be usedas a source of energy. This method does not require high heads of waterfor efficient operation.

A system 25 for the generation of power is shown in FIGS. 1 and 2. Aflotation tank 26 is supported on a suitable foundation, such as theearth, at an appropriate elevation between the water supply and drain.The tank has a bottom 27, a peripheral sidewall 28, and an open top 29which forms an open-topped flotation cavity 30.

A supply inlet pipe 31 conveys water from supply 20 to cavity 30. It mayenter the tank at any elevation, and even discharge over the upper edgeof the sidewall if the relative elevations permit, but less turbulenceand splashing occur if the filling takes place under water. An off-oninlet valve 32 controls flow of water through pipe 31. A drain pipe 35drains water from the cavity. It must be capable of draining theflotation tank to a level at or below lower drain elevation 22. Controlover flow through the pipes will be fully disclosed below.

In the operation of this invention, the water level in the tank willcycle between upper elevation 21 and lower elevation 22. The level ofthe outside supply and of the ultimate drain remain substantiallyconstant. A weight means 50 having mass is, as a total body, buoyant inwater, i.e., its average specific gravity is less than that of theliquid in which it is to float. The weight means may be a body 51 madeof a single buoyant material such as wood, or it may be a composite bodymade of both light and heavy materials, such as a combination of a steelcore and a foam coating, or it may be a floatable structure, such as ahollow steel ball, or a boat which may or may not carry weights. In anyevent, the weight means has mass, and can be buoyantly supported inwater.

For the optimum usage of a low head of water, the average specificgravity of the weight means will be close to the specific gravity of thewater (fresh or sea water) in which the weight means is to be floated.

It is the objective of the water cycling to flood water into the tank soas to float and raise the weight means, and then to recede to permit theweight means to descend without substantial impediment except frompressurizing means yet to be described. In order to raise the weightmeans to the illustrated level, the water will have to rise to a level21 below the top of the weight means because the buoyant structure willrise somewhat above the surface of the water. In order to permit all ofthe potential energy of the weight means to be recovered, the lowerwater level 22 will be at or somewhat below the bottom of the weightmeans so there will be no buoyant effect on the weight means at any timeduring its descent.

For convenience in disclosure, the weight means is shown as a buoyantflat slab with a planar bottom 52. Certain elevations are shown relativeto an arbitrary datum line 53. L₁ is the minimum upper elevation of thewater supply (elevation 21), and is the highest water level permitted inthe tank. L₂ is the maximum elevation of the lower drain (elevation 22).L₃ is the lowest elevation of the bottom of the weight means, and L₄ isthe highest elevation of the bottom of the weight means. There ispreferably a difference, Δ₁, between L₂ and L₃ which represents a smallclearance between the bottom of the weight means and the water at itslowest level which assures that the weight means will not be supportedby water during its downward movement. Δ₁ may be zero if care is takenthat water is not displaced by the weight means in its lowermostposition.

There is a second significant difference in elevation, shown as Δ₂,which is the difference between L₁ and L₄. This is the height the waterlevel must rise above the bottom of the slab to lift it, i.e., this isproportional to the volume of water displaced by the slab when itfloats. Therefore, the potential energy in the weight means in footpounds is the weight of the slab times the difference between L₄ and L₃.Δ₁ will be kept as small as possible, because it represents a waste ofenergy.

Four pressurizing means 60, 61, 62, 63 are supported on the bottom ofthe tank. It is convenient for them to be under water, but it is notnecessary. Pressurizing means 60 and its connection to the slab areshown in detail in FIG. 1. The other pressurizing means are alike, andthey are, therefore, not described individually in detail.

A socket member 65 is sunk in the bottom of the weight means. A socket66 is formed in a sleeve 67 on the socket member. The sleeve has across-passage 69.

Pressurizing means 60 includes a cylinder 70 having an internal rightcircular cylindrical wall 71 and a pair of end plates 72, 73. A piston74 makes a sliding, fluid-sealing fit with wall 71. A peripheral seal 75around the piston makes the seal between the piston and the wall. Apiston rod 76 is attached to or integral with the piston. It passesthrough a passage 77 in end plate 72. A packing 78 seals around the rod.The piston and cylinder constitute an "enclosure" which bounds a pair ofchambers 79, 80. The piston and cylinder are sometimes referred to as a"first and second portion", at least one of which is movable relative tothe other by means of a force applied to one of them (this is sometimesreferred to as a "force applied to the pressurizing means"). In theillustrated embodiment, the force is applied to the piston. The volumeof the chambers can be reduced by a force applied to the illustratedpiston. Obviously, the cylinder could be attached to the rod and thepiston held stationary.

A bumper 81 is placed in the bottom of the cylinder to prevent thepiston from bottoming out. A collar 82 is placed atop the cylinder,against which the weight means can bear if it is not supported by waterin the tank.

A removable cross-pin 83 joins the weight means to the piston rod bybeing inserted into cross-passage 69 in the socket member, and into across-passage 84 in the rod. By means of this connection, force exertedby the weight means in moving either upward or downward, is transmittedto the piston rod. The piston rod is sometimes referred to as "forcetransmission means", because it transmits the force from the weightmeans to the piston.

Cross-pin 83 can be removed to separate the weight means and the rodwhen maintenance is required. This situation is shown in FIG. 6, where achain 85 that is attached to the tank is hooked to an eye bolt 86affixed to the weight means to suspend the weight means in the air. Thehook 87 is at a lower level than the uppermost level which the eye boltreaches when the tank is full. At that time, the hook on a slack chainis engaged to the eye bolt. Then the water is drained. The weight meanswill descend until the level illustrated in FIG. 6 is reached, and willthen be suspended by a plurality of the chains. The pin is removed, andthe piston and rod will descend. The tank may be drained and maintenancecan readily be performed. When the tank is refilled to a level where theweight means again floats to the upper elevation, the chains will againgo slack, and the hooks can readily be disengaged so the operation ofthe pressure source can resume.

Pressure ports 90, 91 pass through the wall of the respective chambers79 and 80. Each is joined to a respective manifold 92, 93. As best shownin FIG. 3, lower manifold 92 is fed by runners 94, 95, 96, 97 from thelower chambers 79 of respective pressurizing means 60, 61, 62, and 63.Upper manifold 93 is fed by runners 98, 99, 100, 101 from the upperchambers 80 of the same respective pressurizing means. Manifolds 92 and93 are sometimes called "conduits".

Manifolds 92 and 93 discharge respective streams of water under pressurethrough nozzles 105 and 106 (FIGS. 4 and 5). Potential energy for thisfunction is secured by raising the weight means buoyantly in the tank byadmitting water to the tank for this purpose, and then draining thewater. The deadweight of the weight means is used to reduce the volumeof the lower chamber, and the weight means is preferably permitted todescend without substantial impediment other than the pressurizingmeans. The nozzles act as restrictions on the rate of descent, and asmeans for shaping the stream. It is evident that the most effectivestroke of the piston is on its descent (downstroke) wherein the fullweight of the weight means is effective to reduce the volume of chamber80. A single-stroke construction may be provided in which only thedownstroke is used. In such a case, the second manifold 93 would beomitted, and the upper chamber will be ported to permit free inflow andoutflow of water between the upper chamber and the tank.

However, some work can be extracted from the upstroke, even though it isconsiderably less than that which can be derived from the downstroke. Itis derived only from the buoyant forces that lift the weight means. Thiswork, even though less, may still be put to use. One such use is shownin FIG. 1, wherein the second manifold is used to supply nozzle 106,whose discharge stream does the same kind of service that the streamfrom nozzle 105 does. It might instead be used to provide pressure (orpower) for auxiliary functions, such as valve or gate actuators or thelike.

Cycling means is provided for alternatively admitting water to the tankand draining it from the tank so as to move the water level fromelevation L₁ to elevation L₂ and return, moving the weight means througha cycle equal to a rise and fall of the difference between elevations L₃and L₄. The function of the cycling means is to fill a low tank and todrain a full tank, and preferably to allow the weight means to descendwithout impediment other than the pressurizing means.

The filling function is controlled by inlet valve 32. This valve has twostable positions, open-to-flow (open), and closed-to-flow (closed). Itis controlled by an actuator 110 which includes a pivoted arm 111 havinga hole 112 through which a flexible cable 113 with a weight 114 at itsfree end passes. The cable is connected to the weight means, and passesover a pair of guide wheels 115, 116. The weighted arm of the cablerises and falls inversely with the rise and fall of the weight means inthe tank.

A pair of strikers 117, 118 are fixed to the cable at appropriatepositions. Striker 117 is placed so that it will move arm 111 to openthe valve when the weight means is at its lowermost desired level in thetank. Striker 118 is placed so that it will move arm 111 to close thevalve when the weight means has reached its uppermost desired level. Thearm remains at its last position while the weight means is moving to thenext of its said two levels.

Drainage to level L₂ can be accomplished by valving, as will later bedisclosed. However, an elegantly simple drainage device is anintermittent siphon 120 (FIG. 1). This siphon has a short leg 121, abend 122 with an upper point 123, and a longer leg 124 leading to adrain port through the side of the tank. The lower end 125 of the shortleg is at elevation L₂, and when the water surface reaches this level,air will be drawn into the siphon, which stops the siphoning action.

Point 123 is located about at level L₁, and siphoning will resume whenthe siphon has been refilled to this level as a consequence of therefilling of the tank. The intermittent siphon has the significantadvantage that no moving parts are needed.

Should more positive control of drainage be desired, then instead ofusing an intermittent siphon, a drain valve 130 may be placed in thesame or another drain pipe 131. It may be identical to valve 32 and canbe controlled by the same actuator. It is open-to-flow when valve 32 isclosed-to-flow, and vice versa. Valves 32 and 130 are, therefore, inpush-pull, or inverse, relationship to one another.

The combinations of valve 32 and the intermittent siphon, or of valves32 and 130, together with any control means they utilize, is sometimescalled "cycling means". Their portions which control drainage of thewater are sometimes referred to as "means to release the weight means".

The term "pressure source" as used herein includes the combination oflift means (flotation tank and inlet and outlet controls), weight means,pressurizing means, and, where used, force transmission means fortransmitting force from the weight means to the pressurizing means (ormore precisely, to a movable portion of the enclosure that bounds thechamber). It constitutes a source of a stream of liquid under pressurewhich can be used as a source of power. The term "stream" is not limitedto flow through a nozzle, although that is one of its connotations.Instead, it means a quantity of liquid under pressure movable so as todo work. Flow to or in a linear or rotary hydraulic actuator or motor isincluded in the term "stream".

FIG. 3 shows the presently preferred means to utilize the stream ofliquid. It is used as a nozzle discharge in a system that includes aturbine 135 and an electrical generator 136 driven by the shaft of theturbine. Classical turbine and nozzle criteria may be employed inmatching the components of the system to its output pressure andvolumetric capacity. It is pertinent to note at this point that thepressure of the output pressurized stream will be substantiallyconstant, because the piston is either driven downward by a descendingdeadweight of constant mass, or by an upward buoyant force on a constantmass. The nozzle dimensions are, of course, constant, and comprise theprincipal restriction on the rate of descent of the weight means. Infact, the weight means will be supported while falling by the upperforce derived from pressure in the cylinders, and this is, of course,determined principally by the restriction of the nozzle. This is themeaning of the phrase that the descent of the weight means occurswithout substantial impediment other than the pressurizing means. Theweight means can descend only as rapidly as flow from the pressurizingmeans will permit.

Considerable simplification of the system is attained if the fluidexpelled from the chambers does not have to be replenished from theflotation tank. Because these systems are intended to be asmaintenance-free and rugged as possible, some minor losses in efficiencycan be tolerated to achieve this objective. To achieve this objective,the chamber will be refilled with water which was previously expelledfrom it.

The turbine 135 is mounted to a pair of bearing blocks 137, 138 (FIGS. 4and 5) and has a shaft 139 with an axis of rotation 140. Bearings 141,142 mount the shaft for rotation around its axis of rotation 142a. Abucket wheel 143 is fixed to the shaft, and includes a procession ofbuckets 144 having drive surfaces 145 spaced apart around the said axis.When the bucket wheel and shaft rotate, the drive surfaces successivelycross the path 146 of the stream 147 emitted from the nozzle, and theturbine wheel is thereby driven. This class of turbine can be used withor without the water supply feature described in the next paragraph.

A water-filled pan 150 is placed beneath the turbine wheel, and thenozzle or nozzles is or are submerged just beneath the surface 151 ofthe water. The nozzle port is not so deep as seriously to impede ordestroy the shape of the nozzle stream--it readily breaks through areasonable depth of water, such as 1/4 to 1/2 inch for many practicalstreams, to impinge upon and drive the turbine wheel when the volume ofthe respective chamber is being reduced. When this piston is on itsreturn stroke for the respective chamber, water will be drawn into thechamber from the pan through the nozzle, rather than through valvingsystems from the tank into the cylinder. This can constitute aconsiderable simplification of construction. Of course, valving systemsto admit water to the chambers from the flotation tank, and to precludebackward flow through the nozzles during the intake stroke, can readilybe devised by persons skilled in the art should one wish to use them.Then submersion of the outlet end of the nozzle would not be required.

The two sets of nozzles may discharge side by side, or against separatewheels fixed to the same shaft, as preferred.

Generator 136 is conventional, and provides electrical potential at itsoutput leads 152, 153. Conventional speed controls or brakes may be usedto regulate the turbine speed, or, if desired, an adjustable valve 154may be placed in the manifold to adjust the rate of flow to the turbineindependently of the nozzles. Also, the angle of attack of the streamagainst the buckets can be adjusted on an intermittent or running basisfor speed regulation.

The attainable flow rate through the drainage means should besufficiently fast that the water will recede below the bottom of theweight means as quickly as possible. Then the force of the downwardstroke will not be reduced by buoyancy. It is a substantial advantage ofthis invention that the full constant downward force of a lifted weightcan be applied to the pressurizing means. If the outflow rate issufficiently great, a small overlap of downward movement and buoyantlift at the top of the stroke is not intolerable, because the waterlevel will be underneath the weight means before the weight means hasfallen very far. Also, some overlap at the bottom of the descent istolerable. Both situations are within the scope of the invention. If onewishes to avoid overlap at the upper elevation, then a level-sensingvalve 155, such as an off-on ballcock valve (FIG. 7), can be placed inthe manifold 92 so as to prevent flow through the manifold until thewater level in the tank has fallen to some control level well below theweight means and well below the upper elevation. FIG. 7 shows a float156 in such a valve pivotally mounted near a control level where, whenthe water level is above the control level, it will rise to the positionshown in dashed line and close valve 155 to prevent flow through themanifold. Then liquid trapped in the chamber 79 will support the weightmeans and prevent its descent. When the water level has fallen to thecontrol level, the float will have moved to the position shown in solidline. The valve will then be opened, flow through the manifold canstart, and the weight means can descend. Valve 155 thereby constitutesmeans to release the weight means for descent when the water level haslowered to an agreed elevation, usually beneath the weight means.

FIG. 8 illustrates that constructions other than piston-cylinderassemblies are useful as pressurizing means. A diaphragm pumpconstruction is shown in this FIG. which includes a cylinder 160 closedat its top by an elastic diaphragm 161. A plunger 162 is fixed to rod 76of FIG. 1 instead of a piston, and the two limiting positions of thediaphragm are shown. The upper dashed line position is the relaxedcondition of the diaphragm. The weight means is fully raised at thistime. The solid-line position is assumed when the weight means hasdescended to its lower limit. The chamber 163 has a variable volumewhich is reduced when the diaphragm ("movable portion") is moveddownwardly. The cylinder and the diaphragm comprise an enclosure andalso the two portions, at least one of which is movable. The fluid flowis the same as that from chamber 79 in FIG. 1 wherein a piston andcylinder are used.

Should water from the tank be used to supply water to the pressurizingmeans, then the chambers will be provided with another port having aunidirectional check valve permitting flow of liquid into the chamberfrom the tank cavity, but not the reverse, and another unidirectionalcheck valve in the manifold, permitting flow toward the nozzle, but notthe reverse. The pressurizing means would then act as a commonunidirectional pump. In addition, the relative elevations would beselected to prevent gravity flow through the two check valves.

The embodiments heretofore described have provided a major stream on thedownward movement of the weight means, and optionally a second, lesser,stream on the upward movement thereof. The use of a single-tank pressuresource in this manner relies on a flywheel inertial property in thesystem downstream of the nozzles to keep running until the next downwardmovement of the weight means. While this is a valid method of operation,improved performance will usually result if two or more tanks are usedsequentially so that there is little or no interval between pressurestreams at the nozzles. One such arrangement is shown in FIG. 9.

In FIG. 9, there are shown two tanks 170, 171, each with respectiveweight means 172, 173, four pressurizing means 174-177 and 178-181, andconduits 182-189 leading to the individual nozzles. Only nozzle 190 isshown, the others being parallel to and behind it or hidden by it inFIG. 10. The nozzle arrangements may be as previously described below orout of water depending on how water is supplied to the chambers. Weightmeans 172 and 173 are buoyant.

A shaft 191 has a horizontal axis of revolution 192. There are eightturbine wheels 193-200 fixed to this shaft. Each wheel has buckets withdrive surfaces which successively intersect the stream of liquid fromthe respective nozzle to drive the shaft as in FIGS. 1-4. This FIG. alsoillustrates that the outputs from the pressurizing means need not bemanifolded, but instead can be discharged from individual nozzles toindividual wheels rather than to a single turbine wheel, if preferred.

The details of the water supply and drains, and of the cycling means,will not be repeated here. Construction and considerations identical tothose used in the system of FIG. 1 will be used. There is shown,however, a means for preventing the simultaneous filling of the twotanks, which, assuming proper overall system design and proportioningwill also substantially synchronize the operation of the two tanks sothat one is lifting its weight means while the weight means isdescending in the other, and vice versa. This control is a selectorvalve 205 disposed in the inlet pipes 206, 207 from the water supply tothe respective tanks. Selector valve 205 is under the control of one ofthe weight means the same as inlet valve 31, and valve 205 is sometimesreferred to as an inlet valve for both of tanks 170 and 171. It issolely under the control of weight means 172, and therefore, tank 171acts as a slave to tank 170, filling only when tank 170 is not filling;that is, selector valve 205 directs the flow alternately to one tank orthe other. The drainage of the tanks will be alternated imilarly, usingslave valving, i.e., valves such as valve 130, also under the sameinverse control, or the intermittent siphons, as preferred.

The foregoing is only one example of means sequentially to operate twotanks. More than two tanks can obviously be used and the weight means ofone or more can be raised and held at the upper elevation, pending itsturn to descend. Other sequencing means, and even manual means, canreadily be devised by a person knowledgeable in this art, and no furtherdiscussion will be given here. Suffice it to say that FIGS. 9 and 10show means for the sequential operation of a plurality of sets ofpressurizing means to provide a substantially constant source of fluidunder pressure to a turbine or other means which utilizes the streamfrom the pressurizing means.

In FIGS. 1-10, the lowering of weight means, and sometimes also theirraising by buoyancy, is used immediately and continuously to drive ashaft by means of a turbine wheel or other device. This quite closelycouples the operation of the tanks to the operation of the shaft drive.It is possible to de-couple these, and still to use the water (eitherbuoyantly or by other means yet to be described) to raise weight means,and accumulate the weight means at an upper elevation to be loweredindividually afterward at intervals and times which have no necessarycorrelation with the flow of water used to lift the respective weightmeans in the first place. One such system is shown in FIG. 11.

In this system, two tanks 220, 221 are provided with the same cyclingcontrols as shown and suggested above for raising and lowering the waterlevel therein. Similar supply and drainage provisions are made, and thedescriptions and illustrations thereof will not be repeated.

Lift means 222, 223 is provided in each tank. Because these lift meansare mirror images, only lift means 222 will be described in detail. Itis shown in FIG. 13. Lift means 222 includes a buoyant body, such as afloat, a tank, or a barge 224. Risers 225, 226 support a pair ofparallel rails 227, 228. When the float is level, the rails slopedownward and to the right in FIG. 13. A slope 229 is formed on thebottom of the tank with its highest part at the right in FIG. 13. Itsslope is double that of the rail. It is the function of the buoyant bodyto receive balls 230 ("weight means") on the rails at a lower elevationand lift them to an upper elevation where they can be stored and used atleisure, or at a closely coupled rate, if preferred.

When the buoyant body rests on the bottom of the tank, its rails slopedownward and to the left in FIG. 13. The balls then roll against a stop231. When the float rises and is level, the rails slope downward and tothe right so they will roll off. A stop 232 holds the loaded balls onthe track until time for their release. Rails 232a, 232b restrain thefloat in a level position at the upward limit of its travel, and thefewer balls there are aboard, the greater the buoyant force against therails for this purpose. A portion 233 of rail 228 is eliminated so theball can roll off the body sidewise. A gate 234 prevents this movementuntil it is desired. This gate comprises a pivoted arm 235 with a finger236 which, when elevated, prevents the ball from rolling off. Acontactor 237 on the arm is adapted to strike an actuator pin, yet to bedescribed, to lower finger 236 and let one ball roll off at a time.

The power source of this embodiment also includes a beam 240 that ispivotally supported by a cross-shaft 241. The cross-shaft in turn issupported by a pair of posts 242, 243. A bearing 244 mounts the beam tothe cross-shaft. The bearing is fixed to the beam.

Two pressurizing means 245, 246 rest on a foundation. They include rods247, 248, respectively, which are pivotally pinned to yokes 249, 250carried by the beam. Rocking of the arm will reciprocate the rods up anddown, and actuate the pressurizing means. Any of the pressurizing meansheretofore described may be used for pressurizing means 245, 246, andthey will not be further described. Conduits 247, 248 lead to respectivenozzles (not shown) which deliver a stream of liquid under pressure. Ifthe underwater type of discharge of nozzles shown in FIG. 4 is not used,then other means to replenish the water expelled from the pressurizingmeans must be supplied. These also have been separately discussed. Asuitable example would be submerging the pressurizing means inrespective tanks and keeping these tanks filled as a source of water,just as was described for the systems in FIGS. 1-10.

Similarly, a drive 251 comprising a turbine of the type described aboveis driven by the stream, and drives an electrical generator 253.

A counterweight 255 is placed at one end of the beam. It will be lighterthan the individual balls. For example, if each ball weighs 1000 lbs.,the counterweight should weigh 500 lbs., when each is the same distancefrom the cross-shaft (acting as a fulcrum). When a ball is on the otherend of the beam, there is a net torque of 500 lbs (the 1000 lb. ballminus the 500 lb. counterweight) times its distance from the shaft in acounterclockwise direction. When the beam has reached the lower limit ofits motion, the ball rolls off onto the other lift means, which isresting on the bottom of its own tank. Then there is a net torque of 500lbs. times the distance from the shaft exerted by the counterweight in aclockwise direction, and the beam rotates clockwise. A rocking motioncan thereby be developed by sequentially loading and unloading ballsfrom the left-hand end of the beam in FIG. 12.

If the balls are to be stored and not used by the beam directly from therails, the balls can be rolled off onto storage racks (not shown), andused from there in the same manner. In either event, means will berequired to load and unload the ball on and off the beam. Such a meansis shown in FIGS. 12 and 15. Gate 234 on lift means 222, and a like gate(not shown) on lift means 223 will adjoin the end of the beam when thebeam is in the respective upper or lower position. The beam carries arocking saddle 257. The saddle is mounted to a trunnion 258 and has atrough 259 to receive a ball and cradle the ball when the saddle iscentered by centering springs 260, 261. Actuator pins 262, 263 projectfrom the saddle. As best shown in FIG. 13, the actuator pin can strike acontactor when the beam is in its raised condition to open the gate andpermit a ball to roll onto the saddle from rails at their uppermostelevation. A stop 264 is attached to the buoyant body and disposed at alower elevation to catch pin 262 and rock the saddle to spill the ballonto a set of rails at a lower elevation. A duplicate gate and stop isprovided on the other set of rails to function when the other set ishigh and the first set is low. Thus, the balls can be cycled back andforth from one buoyant means to the other as they are alternativelyraised and lowered.

Loading of balls onto the beam from a stationary platform, and unloadingthem onto rails or platforms, can be performed in the same way. Loadingand unloading of balls onto and off of the rails from the platforms mayalso be analogously accomplished. The pertinence of this system is that,as contrasted with the systems of FIGS. 1-10, the tank can be raisingweight means with a different frequency than is utilized by thepressurizing means.

The systems of FIGS. 1-10 illustrate that the buoyant means for liftinga mass (weight means) can be a buoyant mass itself which is directlyused while in a tank to drive a pressurizing means.

The system of FIG. 11 illustrates that the buoyant means can be used tolift different and separate weight means which may be non-buoyant.

The system of FIG. 16 illustrates that inherently buoyant weight meansfor use away from the flotation tank can be buoyantly lifted by meanswhich do not require a cyclic raising and lowering of a water level. InFIG. 16, a tank 270 (it may be a cylindrical standpipe) is supplied withwater to an upper level 271. At a lower level, an injector slide 272passes diametrically across the tank and makes a sliding fit therein.Seals 273, 274, 275 in fittings 276 and 277 seal around the slide toprevent leakage past it. The slide has a pocket 278 to receive buoyantballs 279 (weight means). The fittings are longer than the pockets, andthe spacing between seals 273 and 274 is also longer to minimize waterloss. A drain port 280 drains the pocket when outside of the tank.

To inject a ball into the tank, the ball is first loaded into the pocketwhile outside of the tank, and the slide is shifted to move the pocketinside the tank, where the ball floats to the top. The slide is thenmoved to place the pocket outside the standpipe to receive the nextball. An amount of water at least equal in volume to that of the ball islost from the tank for each cycle and must be made up to maintain thewater level in the tank. Only the energy needed to overcome functionallosses needs to be exerted on the slide to inject the balls. The ballsare removed from the tank at the upper level through locks (not shown).

FIG. 17 illustrates that weight means for use in a system such as thatshown in FIG. 11 can be raised by a water lift but without utilizing itsbuoyancy for the purpose. For this objective, lift means 285 comprises aconventional bucket wheel 286 having buckets 287 swivelly mountedthereto to receive water at an upper elevation and dump it at a lowerelevation. The wheel is rotatably mounted to a shaft 288. The wheel alsocarries ball supports 289, and receives balls 290 (weight means) at alower elevation and dumps them onto a platform at an upper elevation forusage in a system such as that shown in FIG. 11.

A latch 291 (release means) holds the bucket wheel against rotationuntil enough water has been placed in a respective bucket to lift theball. Then it releases the wheel to allow it to lift the ball. The latchincludes a latch pin 292 which is movable into and out of the path of alatch groove 293 on each arm 294 of the wheel. A lever 295 pinned to thelatch pin can withdraw it against the tension of a spring 296 when atrigger 297 rotates under the weight of water spilled from a full bucketfor this purpose.

The bucket has a lip 298 which spills water 299 onto the trigger (orinto a cup held by the trigger) so that the weight or force of the waterrotates the trigger counterclockwise in FIG. 17 to pull the latch pin.The weight of the full bucket will turn the wheel, and raise a ball 290in the ball support to the upper level of a ramp 300 which receives it.The arms act as levers around shaft 288, which acts as a fulcrum.

A dump valve 302 in the bottom of each bucket includes a valve actuator303 which hangs vertically to keep the dump valve closed except when thebucket is at the bottom of the wheel. There it contacts a fixed strikerplate 304, and is deflected sideward to open the valve and drain thebucket.

FIGS. 18 and 19 illustrate that the container for water need not itselfchange elevation when water is used as the weight means, but only thebody of water itself. In this embodiment of pressure source, a tank 310has a peripheral sidewall 311 and a bottom 312. An inlet valve 313 andan outlet valve 314 control flow into cavity 315 formed above a flexiblediaphragm 316 that extends across the cavity above the bottom. The waterrests on this diaphragm.

The diaphragm can assume an upper position shown in solid line, and alower position shown in dashed line. A pressurizing means 320 isidentical in all respects to those described above. It discharges into aconduit 321 which can be any of the conduits or manifolds previouslydescribed to receive a stream from the pressurizing means.

Rod 322 constitutes force transmission means, and includes a backingplate 323 which underlies the central portion of the diaphragm and isbacked up by a return spring 324. Spring 324 is in compressiveopposition between the bottom of the tank and the backing plate. Ventports 325 vent the region in the tank below the diaphragm.

A latch (release means) 330 includes a forked yoke 331 which slides on abase 332 and, in its position shown in FIG. 18, embraces the rod below acollar 333 that is fixed to or is part of the rod to hold the rod anddiaphragm in an upper position.

A force actuator 335 includes a body 336 and a flexible diaphragm 337extending across the body to form a closed chamber 337a. The diaphragmis opposed by a spring 338 which biases the yoke to the illustratedlocked position. A pressure conduit 339 interconnects the region of thetank just above the diaphragm to chamber 337a so that, when apredetermined amount of water is placed in the tank, the pressureconduit transmits the respective pressure to the chamber, and moves thediaphragm to pull the yoke away from the rod, and the rod can movedownward. The compression in the spring can be adjusted to select thesaid pressure.

A wedge face 340 is formed on the top of the collar, and another face341 on the bottom of the yoke so as to shift the yoke aside when thecollar is raised past it.

FIG. 20 illustrates the direct usage of water as weight means. It isshown actuating a pressure source of the same type as shown in FIG. 11,and like parts are given like numbers. However, instead of having meansto receive discrete balls as weight means, a container 350 is mounted toone end of the beam, where it receives water either in continuous flowfrom a supply line 351, or through an inlet valve 352 in the supplyline.

Latch means 352a identical to that shown in FIG. 18 is provided to holdthe beam in the position shown in FIG. 20 until a predetermined amountof water is placed in the container. A flexible hose 353 connects thecontainer to the latch means to transmit the pressure for pulling theyoke. The hose is long enough to accommodate the full stroke of thebeam.

A drain valve 355 has an actuator 356 which will open the valve and dumpthe container at the bottom of the stroke upon striking an abutmentmeans 357.

FIG. 21 illustrates that the pressure source can drive devices otherthan rotary devices. Manifold 92 is shown connected to a linear actuator360. The best known form of linear actuator is a piston-cylinderassembly. Its rod (or shaft) moves linearly along a linear axis 361, andthis may be used directly as a shaft drive. It may also be used to drivea rotary shaft such as shaft 362 which rotates unidirectionally as shownby arrow 363 by the interposition of a unidirectional transmission means364 such as a one-way clutch. Therefore, oscillating arm 365 will rotateshaft 362. Shaft 362 could be such as the drive shaft of an electricalgenerator.

The operation of the foregoing should be evident from their description,so only a brief recapitulation will be made. In the system of FIG. 1,operation is started by closing the drain valve, if one is used (theintermittent siphon needs no attention), and opening inlet valve 32.Water from the supply will flow into the tank and lift the buoyantweight means. Striker 118 will cause valve 32 to close when the properwater level is reached. When an intermittent siphon is used, the siphonshould start to flow at this time if it is properly adjusted andproportioned. if a drain valve is used, it will be opened. This willpermit water to leave the tank and recede from the weight means.

It is possible to eliminate the inlet valving if the rate of inlet flowis slow enough as not to impede the operation of the pressurizing means.However, such continuous flow does constitute a waste of potentialenergy.

If the rate of drainage is sufficiently high and the rate of descent ofthe weight means sufficiently low, the manifold or manifolds need not beprovided with valving to hold the weight means against descent untilreleasing them for descent after the water has receded to a suitably lowelevation. A minor overlap of weight descent and receding water isundesirable, but not intolerable. After the water has receded below theweight means, the pressure in the pressurizing means is dependent onlyon manifold and nozzle conditions, and the deadweight of the weightmeans. It is substantially constant, and this is a considerableadvantage in operating turbine wheels, because the pressure and flowrate of the stream can be adjusted to optimum conditions.

The operation of the turbines in FIGS. 4 and 5 is conventional. Thebuckets sequentially intersect the stream and are driven by it. Agenerator or other device can be directly coupled to the driven shaft ofthe turbine.

The refilling of the pressurizing means through the nozzle is evidentfrom FIG. 4.

FIG. 5 shows the usage of pressure streams from both chambers 79 and 80to drive a turbine wheel. The lesser flow from manifold 93 could,instead, be accumulated and used for auxiliary functions, if preferred.

In FIG. 7, valve 155 will close its respective conduit or manifold untilthe water in the tank has receded to a control level. Then it will opento allow flow from the chamber. Until this valve (when used) is opened,the weight means cannot descend. A one-way check valve 155a permits flowtoward the chamber on its intake stroke even when valve 155 is closed.This is another means to restrain the weight means until the water hasreceded below it so as to assure that there is no buoyant forceresisting the descent of the weight means.

The pressurizing means of FIG. 8 can be used wherever a piston-cylinderassembly can be used.

The operation of the individual pressure sources in FIGS. 9 and 10 isidentical to that of FIG. 1. FIGS. 9 and 10 merely illustrate thesequential operation of a plurality of them in driving a common turbineshaft. The selector valve 205 provides for alternate (or sequential)filling of the flotation tanks.

In FIG. 11, one of the flotation tanks will be filled and the otheremptied. Then balls from the raised lift means are released, one by one,to the end of the beam when it is up and adjacent to the rails. The gatewill release a ball at a time as previously described. The ball willforce the end of the beam downward until it reaches the level of thelower rails, at which time the saddle is tilted to roll the ball off ofthe saddle and onto the lower rails.

When all of the balls are removed from the upper rails, the respectivetank is drained and the buoyant body will rest on the bottom awaiting anew supply of balls to be lifted. The other tank is filled to raise theballs and provide a new supply. The process continues indefinitely. Theoperation of the individual components should be evident from theirprevious description.

The lift means of FIG. 16 operates as previously described. The slidetakes relatively little energy, because there are no unbalanced endforces on it. Energy from manifold 93 would be a suitable source tooperate the slide.

The lift means of FIG. 17 operates as previously described, and lifts aball each time a bucket is filled with water. The relative spacing ofthe cups and buckets along the arms of the wheel can be adjusted toprovide lesser, additional, or no, leverage, as desired.

In FIG. 18, water is charged into and drained out of the tank 80 as tochange the level of the backing plate and run the pressurizing means. Inthis embodiment, release means is of particular utility. The releasemeans shown in FIG. 18 is the mechanical equivalent of a valvedownstream from the pressurizing means. It may be used in place of thevalving and control of FIG. 7, and the valving and control of FIG. 7 canbe used in place of the mechanical latch. Both comprise "release means."

After the cavity has been filled to the proper level, the release meanspermits the rod to descend, applying force to the pressurizing means.Then, at the end of the descent, the cavity is drained. The returnspring returns the diaphragm to the upper position, the cavity isrefilled, and the cycle is repeated.

The pressure source of FIG. 20 directly utilizes the weight of water,rather than using the water to lift a solid mass. Except for thisdifference, it operates in the same manner as the system of FIG. 11.

FIG. 21 is a further illustration of the general utility of the pressuresource.

The term "force transmission means" as used herein means anyinterconnection or linkage which transmits force from the weight meansto the pressurizing means.

In the operation of pressure sources wherein a buoyant body descends inthe flotation tank to drive the pressurizing means, it is preferable tokeep the water level below the bottom of the weight means while itdescends so the force is proportional only to the mass of the weightmeans. Such operation is totally analogous to the lowering of a ball inthe air in FIG. 11, or of the body of water in FIG. 18. It has theadvantage that the downward force is not diminished by an upward buoyantforce. This class of operation is described by the terminology"releasing, in discrete quantums of mass, weight means for downwardmovement without substantial impediment other than the pressurizingmeans."

However, it is possible, although not desirable, to lower the waterlevel at some rate which is equal to what will be a lesser rate ofdescent, partially supporting the weight means of buoyancy. The neteffect of such operation is to exert a lesser downward force, anoperation which is equivalent to using a lighterweight means in thefirst place. Therefore, this is analogous to adjusting the mass of theweight means. Such a method of operation, and the mechanism to carry itout, are also included in this invention. It constitutes a control ofthe rate of flow to drain.

The term "discrete quantum of mass" connotes the fact that this pressuresource is not intended to operate unless there is a predetermined weightwhich will produce a predetermined pressure in the pressurizing means.This system utilizes the deadweight of a mass, rather than a head ofliquid, or the velocity of a stream, for energy. Therefore, its energysupply is, in one way or another, accumulated as an elevated mass in adesired quantum before the pressurizing means is operated.

The term "tank" is used in its broadest sense to mean any structure orarrangement wherein the depth of water can be varied so its surfacerises and lowers.

The lift means which have been described all use water to raise aweight, or use already-raised water directly. It is evident that liftmeans for use with this pressure source could use other types of energy,such as windmills to pump water or directly geared to lift weights.

This invention is not to be limited by the embodiments shown in thedrawings and described in the description, which are given by way ofexample and not of limitation, but only in accordance with the scope ofthe appended claims.

I claim:
 1. A pressure source comprising: pressurizing means comprising an enclosure which bounds a chamber, said enclosure comprising a first and second portion, at least one of which is movable relative to the other as a consequence of a force applied to one of them so as to reduce the volume of the chamber and thereby to place under pressure liquid which is contained therein; a conduit leading from said chamber through which a stream of said liquid under pressure can flow for use in doing work; a flotation tank adapted to contain liquid at an upper and at a lower elevation; weight means floatable buoyantly in the liquid in the flotation tank; force transmission means so disposed and arranged as to apply force from elevated weight means to said one portion cycling means for controlling the supply of liquid into, and the drainage of liquid out of, the flotation tank so as respectively to raise the weight means and to permit it to descend; and release means to delay the descent of the weight means whereby the weight means can descend at a rate which is independent of the level of the liquid in the flotation tank.
 2. A pressure source according to claim 1 in which the release means releases the weight means only in discrete quantums of mass of at least a predetermined weight.
 3. A pressure source according to claim 2 in which said release means is a valve in the conduit.
 4. A pressure source according to claim 3 in which level-sensitive means actuates said release means in response to receding of the level of the liquid in the flotation tank to an elevation where there is no substantial buoyant force on the weight means.
 5. A pressure source according to claim 1 in which a nozzle is connected to said conduit from which the stream is discharged.
 6. In combination: a pressure source according to claim 1, and a shaft drive having a rotary shaft to be driven.
 7. A combination according to claim 6 in which the said shaft drive comprises a turbine having a turbine wheel with buckets that bear drive surfaces to be impinged on successively by the stream as it turns the turbine wheel.
 8. A combination according to claim 7 in which a nozzle is connected to said conduit from which the stream is discharged.
 9. A combination according to claim 8 in which the nozzle is disposed beneath a liquid surface so that the stream can break the surface and apply pressure to a body spaced therefrom, and whereby liquid can be drawn into the chamber through the nozzle to be placed under pressure and expelled therefrom.
 10. A combination according to claim 6 in which the shaft drive is a linear actuator.
 11. A combination according to claim 10 in which the linear actuator drives a one-way transmission which in turn drives a shaft.
 12. A combination according to claim 6 further including an electrical generator driven by the shaft drive.
 13. A combination according to claim 6 including a plurality of said pressure sources adapted for sequential cycling.
 14. In combination: a plurality of pressure sources according to claim 1 in which the conduits are manifolded.
 15. A pressure source according to claim 1 in which the said portions comprise a cylinder having a cylindrical wall, and a piston in said cylinder making a sliding fit with said cylinder wall, and in which said force transmission means comprises a rod fixed to one of the said portions.
 16. A pressure source according to claim 15 in which the descent of the weight means occurs without substantial impediment other than the pressurizing means.
 17. A pressure source according to claim 1 in which one of the portions is a body having a cylinder, in which the other one of the portions is an elastic diaphragm extending across the cylinder and forming said chamber, and in which the force transmission means comprises a plunger adapted to press the diaphragm into the cylinder to reduce the volume of the chamber.
 18. A pressure source according to claim 1 in which said cycling means comprises a supply inlet line through which liquid may be supplied to the tank, a drain line through which liquid can flow from the tank, and control means enabling liquid to flow through the drain line only after it has reached a predetermined upper elevation in the tank.
 19. A pressure source according to claim 18 in which the said control means is an intermittent siphon in the drain line.
 20. A pressure source according to claim 18 in which said control means is a drain valve in the drain line, and in which means responsive to water at an upper elevation opens said drain valve to flow when the liquid reaches said upper elevation.
 21. A pressure source according to claim 18 in which the cycling means further includes an inlet valve which controls flow of liquid through the supply inlet line and enables liquid to flow into the tank so as to fill the tank to said upper elevation.
 22. A pressure source according to claim 1 in which the descent of the weight means occurs without substantial impediment other than the pressurizing means.
 23. A pressure source according to claim 1 in which the pressurizing means is beneath the weight means, drainage of the water to a level beneath the weight means while the weight means is at an upper elevation applying the full weight of the weight means to the pressurizing means.
 24. A method of applying force to a pressurizing means of the type which has an enclosure bounding a chamber, the enclosure comprising a first and a second portion, at least one of which is movable relative to the other as a consequence of said applied force to reduce the volume of the chamber, placing liquid contained therein under pressure, and provide a stream of said liquid under pressure, there being force transmission means to apply said force to said pressurizing means, said method comprising: releasing weight means only in quantum of mass of at least a predetermined weight to bear upon said force transmission means, thereby applying said force to the pressurizing means.
 25. A method according to claim 24 in which the weight means is a mass which is buoyantly lifted to an upper elevation for application to the force transmission means.
 26. A method according to claim 25 in which the weight means itself is buoyant in the liquid so as to be floated therein, and in which after raising the weight means, the water buoying it is removed to apply the weight means to the pressurizing means.
 27. A method according to claim 26 in which the weight means is permitted to descend without substantial impediment other than the pressurizing means.
 28. A method according to claim 25 in which the weight means is non-buoyant and raised by buoyant means.
 29. A pressure source according to claim 1 in which said release means is a valve in the conduit. 